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Term Project: Zone Routing Protocol (ZRP). presented by Ikhsan Putra Kurniawan Sun Moon University Spring 2012. Content. Overview of MANET Overview of Proactive vs Reactive Protocol Introduction Zone Routing Protocol (ZRP) Intra-zone Routing Protocol (IARP)
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Term Project:Zone Routing Protocol (ZRP) presented by Ikhsan Putra Kurniawan Sun Moon University Spring 2012 운영체제특론(Advanced Operating System)
Content • Overview of MANET • Overview of Proactive vs Reactive Protocol • Introduction • Zone Routing Protocol (ZRP) • Intra-zone Routing Protocol (IARP) • Inter-zone Routing Protocol (IERP) • Example • A Routing Zone. • Neighborhood Discovery Protocol. • Basic strategy of ZRP. • ZRP with zone radius = 2 . • Interzone Routing. • Route Maintenance. • How to Prevent Flooding of the Network. • Evaluation of ZRP • References 운영체제특론(Advanced Operating System)
Overview of MANET • Mobile Ad-Hoc Network (MANET) • Is a decentralized network over wireless links. • Topology of network is rapidly be changing. • Each node is required to determine the best route to a given destination node by itself. • In wired networks, each link is bi-directional. • MANET does not need bi-directional (unicast, multicast, or hybrid). 운영체제특론(Advanced Operating System)
Overview of Reactive Protocol and Proactive Protocol • A reactive routing protocol tries to find a route from S to D only on-demand, i.e., when the route is required, for example, DSR and AODV are such protocols. • The main advantage of a reactive protocol is the low overhead of control messages. • However, reactive protocols have higher latency in discovering routes. • A proactive protocol maintains extensive routing tables for the entire network. As a result, a route is found as soon as it is requested. • The main advantage of a proactive protocol is its low latency in discovering new routes. • However, proactive protocols generate a high volume of control messages required for updating local routing tables. 운영체제특론(Advanced Operating System)
Introduction to ZRP • Zone Routing Protocol (ZRP) combines the advantage of both pro-active and reactive into a hybrid scheme. • Pro-activediscovery within a n ode’s local neighborhood. • Reactiveprotocol for communication between these neighborhoods. • In MANET most communicationtakes place between nodes closeto each other. • ZRP is provides a framework for other protocols. • to take advantageof each situation (local/global). • “size” of a zone is determined byρ, a radiusof length (number of hops to the perimeter of the zone). 운영체제특론(Advanced Operating System)
ZRP • Peripheral nodes (hc=ρ). • Interior nodes (hc<ρ). • to learn about it’s direct neighbors, a node may use • the media access control (MAC) protocols directly, or • NeighborDiscovery Protocol (NDP) alternatively. • ZRP is infact a flat protocol. • overlapping zones maintained by each individual nodes. 운영체제특론(Advanced Operating System)
Intra-zone Routing Protocol (IARP) • to communicate with the interior nodes. • May rapidly be changing, • pro-active, table-driven protocol. • local route optimization: • removal of redundant routes , • shortening of routes if possible, • bypassing linkfailuresthrough multiple (local) hops. • Support for unidirectional links among the local nodes. • node A can broadcast messages to a node B, but that node B, due to limitations in it’s signal-strength (eg: caused by interference) or low transmission power, can not reach node A. • “limited scope pro-active routingprotocol”. 운영체제특론(Advanced Operating System)
Inter-zone Routing Protocol (IERP) • Route queries are issued on demand. • Border Cast Routing Protocol (BRP). • packet delivery service. 운영체제특론(Advanced Operating System)
K L A B I G S E C D H J Example: A Routing Zone • All nodes except L are in the routing zone of S with radius 2. 운영체제특론(Advanced Operating System)
Neighbour Discovery Protocol • Like other ad hoc routing protocols, each node executes ZRP to know its current neighbours. • Each node transmits a hello message at regular intervals to all nodes within its transmission range. • If a node P does not receive a hello message from a previously known neighbour Q, P removes Q from its list of neighbours. 운영체제특론(Advanced Operating System)
D S Basic Strategy of ZRP • The routing in ZRP is divided into two parts • Intrazone routing : First, the packet is sent within the routing zone of the source node to reach the peripheral nodes. • Interzone routing : Then the packet is sent from the peripheral nodes towards the destination node. 운영체제특론(Advanced Operating System)
C A E B ZRP with zone radius = 2 S performs route discovery for D S D F Denotes route request 운영체제특론(Advanced Operating System)
C A E B S performs route discovery for D S D F E knows route from E to D, so route request need not be forwarded to D from E Denotes route reply
C A E B S performs route discovery for D S D F Denotes route taken by Data
A S C B D H Interzone Routing • The interzone routing discovers routes to the destination reactively. • Consider a source (S) and a destination (D). If D is within the routing zone of S, the routing is completed in the intrazone routing phase. • Otherwise, S sends the packet to the peripheral nodes of its zone through bordercasting. 운영체제특론(Advanced Operating System)
B A Route Maintenance • When there is a broken link along an active path between S and D, a local path repair procedure is initiated. • A broken link is always within the routing zone of some node. • Hence, repairing a broken link requires establishing a new path between two nodes within a routing zone. • The repair is done by the starting node of the link (node A in the previous diagram) by sending a route repair message to node B within its routing zone. • This is like a RREQ message from A with B as the destination. 운영체제특론(Advanced Operating System)
How to Prevent Flooding of the Network • Interzone routing may generate many copies of the same RREQ message if not directed correctly. • The RREQ should be steered towards the destination or towards previously unexplored regions of the network. • Otherwise, the same RREQ message may reach the same nodes many times, causing the flooding of the network. • Since each node has its own routing zone, the routing zones of neighbouring nodes overlap heavily. • Since each peripheral node of a zone forwards the RREQ message, the message can reach the same node multiple times without proper control. • Each node may forward the same RREQ multiple times. 운영체제특론(Advanced Operating System)
A Q B P C X N Termination Strategies (Early Termination of Unnecessary RREQs) • Suppose P has a list of nodes A, B,C,...,N such that the RREQ message has already arrived in the routing zones of the nodes A, B, C, ...,N. • Now P receives a request to forward a RREQ message from another node Q. • This may happen when P is a peripheral node for the routing zone of Q. • P receives a RREQ from Qsince P is a peripheral node for the routing zone of Q. • P does not bordercast the RREQ to A,B,...,N but only to X whichis not in its list. 운영체제특론(Advanced Operating System)
Evaluation of ZRP • When the radius of the routing zone is 1, the behaviour of ZRP is like a pure reactive protocol, for example, like DSR. • When the radius of the routing zone is infinity (or the diameter of the network), ZRP behaves like a pure proactive protocol, for example, like DSDV. • The optimal zone radius depends on node mobility and route query rates. 운영체제특론(Advanced Operating System)
References • http://www.zrp.be • http://www.netmeister.org/misc/zrp/zrp.pdf • www.cs.virginia.edu/~cl4v/PRES_SLI/ZBR.ppt • http://www.drrbpatel.org/lecture/CSE-302-ZRP-Protocol.ppt 운영체제특론(Advanced Operating System)